Thunderbird is a free email program for Windows, macOS, and Linux from the Mozilla community. Besides email, it can work with calendars and address books stored on the server. In this guide we'll add a business mailbox, then connect your calendar and contacts.
What you'll need
- A current version of Thunderbird — download it only from Mozilla's official website.
- Your full email address, for example
name@example.uz. This is also your username. - Your mailbox password.
Server settings for manual setup:
| Setting | Incoming mail (IMAP) | Outgoing mail (SMTP) |
|---|---|---|
| Server | mail.mcmail.uz | mail.mcmail.uz |
| Port | 993 | 465 (or 587) |
| Connection security | SSL/TLS | SSL/TLS (STARTTLS for port 587) |
| Authentication method | Normal password | Normal password |
| Username | full email address | full email address |
If you need POP3, use server mail.mcmail.uz and port 995 with SSL/TLS. We do recommend IMAP, though — see IMAP, POP3, and SMTP for why.
If your administrator has turned on two-factor authentication for the mailbox, check with support on how to connect an email app.
Automatic setup
Thunderbird can find server settings on its own, and MCMail supports automatic configuration (Autoconfig). Usually your address and password are all it takes.
- On first launch, Thunderbird opens the account setup window right away. If you already use it, open the main menu (the three-line button) → Account Settings → Account Actions → Add Mail Account. In some versions this is under File → New.
- Enter your name (recipients will see it), your full email address, and your password. Check "Remember password" if it's your own computer.
- Click Continue. Thunderbird finds and displays the settings.
- Make sure IMAP is selected and the servers match the table above. Click Done.
Thunderbird will then load your folder list and start downloading messages. For a large mailbox, the first sync may take a while.
Manual setup
If automatic setup didn't find the settings or suggested the wrong servers:
- In the same window, click Configure manually.
- Under incoming mail, choose IMAP and enter the server, port, connection security, and authentication method from the table.
- Under outgoing mail, enter the SMTP server, port, connection security, and authentication method.
- Enter your full email address in both username fields.
- Click Re-test. If the test passes, click Done.
Don't set connection security to "None." Without encryption, your password and messages travel in plain text, and anyone on the same network can intercept them.
You can change these settings later in Account Settings: the incoming server under your mailbox's "Server Settings," and the outgoing server under "Outgoing Server (SMTP)" at the bottom of the list.
Calendar via CalDAV
The calendar is built into current versions of Thunderbird — no add-on needed. CalDAV lets you see the same events in Thunderbird, in webmail, and on your phone.
- Get your calendar's CalDAV address. The easiest way is to copy it from SOGo webmail (
https://mail.mcmail.uz): open the calendar view, click the menu next to the calendar name, and look for the item with links to the calendar. You can also ask support for the address. - In Thunderbird, go to the Calendar tab and create a new calendar (the "New Calendar" button or the calendar menu).
- Choose On the Network.
- Enter your username (full email address) and paste the CalDAV address into the location field.
- Click Find Calendars, enter your password, select the calendars you want, and subscribe.
Events you create in Thunderbird will show up in webmail, and vice versa. If colleagues have shared calendars with you, they'll appear in the list too.
Contacts via CardDAV
- Copy your address book's CardDAV address — the same way, from the contacts section of SOGo webmail — or ask support for it.
- Open the Address Book in Thunderbird.
- Create a new CardDAV address book (the new address book button, or File → New).
- Enter your username and the CardDAV address, click Continue, and enter your password.
- Choose which address books to sync.
Contacts will now sync with the server automatically. You can change the sync interval in the address book's properties.
Common problems
| Symptom | Fix |
|---|---|
| "Unable to log in at server" | Verify the password in webmail. The username is the full address. The authentication method is "Normal password" |
| Error when sending | Check the SMTP server and port. If port 465 is blocked on your network, use 587 with STARTTLS |
| Certificate warning | Compare the server name with this guide. Don't add a security exception until you understand the cause |
| Calendar not found | Check the CalDAV address: it must start with https:// and be copied in full |
| Sign-in suddenly stops working | After a series of wrong passwords, brute-force protection blocks sign-in temporarily. Update the password on all devices and wait |
If your mailbox is being moved from another provider, wait until the migration is finished — see our email migration guide. Still have questions? Message us at @mycloudsupport.